bashifparameter

This tutorial aims to help the reader understanding conditions in bash, and provides a comprehensive list of the possibilities.

2023年4月6日 — To display the name of a script when it's run, use a command like echo $0. While anyone running a script will undoubtedly know what script they ...

2023年12月31日 — In this article, I have explored 3 methods to check if an argument exists in bash including different cases.

The [ (or test) built-in evaluates conditional expressions using a set of rules based on the number of arguments. More information about this subject can be ...

2023年1月9日 — The -ne argument of test checks whether the value of the left operand is not equal to that of the right operand. If yes, then the condition ...

2011年6月26日 — If you'd like to check if the argument exists, you can check if the # of arguments is greater than or equal to your target argument number.

We can use different techniques to check the existence of input arguments, such as using the test command, the $# variable, or the -n option.

2018年8月14日 — I would like to check if the first command line argument ( $1 ) has an ... Bash script with command line options gets stuck and doesn't set ...

Within Bash, a special variable, $# , holds the input argument. With $# , you can check how many input arguments have been passed to your Bash script.

If parameter is a nameref, this expands to the name of the variable referenced by parameter instead of performing the complete indirect expansion. The ...